1. Field of the Invention
The present general inventive concept relates to an image forming apparatus, and more particularly to a developing device with a memory unit, and an image forming apparatus having the same.
2. Description of the Related Art
Generally, an image forming apparatus produces an image on a printing medium in accordance with an input image signal. For example, a printer, a photocopier, a facsimile, and a multifunction peripheral (MFP) having combined functions of the aforementioned apparatuses belong to the image forming apparatus.
Especially, an electrophotographic image forming apparatus forms a desired image in the following process. First, a surface of a photoconductive medium is electrified to a predetermined electric potential. A laser beam is projected onto the surface of the photoconductive medium to form an electrostatic latent image. A visible image is obtained by supplying developer to the electrostatic latent image. Next, the visible developer image developed on the photoconductive medium is transferred to a printing medium directly or through an intermediate transferring medium, and then fixed to the printing medium passing through a fusing process.
During the above processes, a developing device of the image forming apparatus forms the visible image on the surface of the photoconductive medium by supplying the developer to the photoconductive device. In general, the developing device is structured as an integrated cartridge including a developer storage unit, an electrifying unit, a developing unit and a cleaning unit, and is detachably mounted to a main body of the image forming apparatus.
Since a life span of the developing device is limited, the developing device has to be replaced when exhausted. In order to favorably operate the image forming apparatus, timely replacement of the developing device is required. For this, a user has to be aware of various information on the developing device as follows.
The developing device is equipped with a memory unit for storing a variety of information on the operation thereof. The information stored in the memory unit may include a residual quantity of developer and a remaining life span of component parts.
The memory unit includes terminals at one side thereof while the main body of the image forming apparatus includes terminals corresponding to the terminals of the memory unit. Upon mounting of the developing device to the image forming apparatus, the memory unit terminals are electrically connected with the image forming apparatus terminals. In a state where the developing device is thus electrically connected to the main body of the image forming apparatus, the image forming apparatus recognizes the information stored in the memory unit, and displays the information for the user or performs any necessary operations using the information and transmits the operation result to the memory unit, thereby updating the information in the memory unit.
In order for favorable data communication between the developing device and the main body of the image forming apparatus, the memory unit should not be damaged and needs to be mounted at an appropriate position for a stable electric connection with the main body.
For example, if the memory unit is disposed around a fixing device which generates a lot of heat, the memory unit would be damaged by the heat. If the fixing device is disposed around the photoconductive medium or developing rollers, the terminals of the memory unit would be easily contaminated by developers scattering about from the photoconductive medium or the developing rollers. This will deteriorate the connection between the memory unit and the image forming apparatus. Furthermore, if the memory unit is disposed at a position such as an upper or lower surface of the developing device often interfered with by other component parts in the image forming apparatus when the developing device is mounted, the memory unit terminals are apt to be damaged during mounting of the developing device.
Moreover, when the memory unit is disposed at a position subject to vibration generated from the developing device in operation, the electric connection between the memory unit and the image forming apparatus becomes unstable due to the vibration transmitted to the memory unit.